2025-11-22
3190. Find Minimum Operations to Make All Elements Divisible by Three

Topic: Array, Math
Difficulty: Easy

Problem:
You are given an integer array nums. In one operation, you can add or subtract 1 from any element of nums.

Return the minimum number of operations to make all elements of nums divisible by 3.

Example 1:

Input: nums = 1,2,3,4

Output: 3

Explanation:

All array elements can be made divisible by 3 using 3 operations:

• Subtract 1 from 1.
• Add 1 to 2.
• Subtract 1 from 4.

Example 2:

Input: nums = 3,6,9

Output: 0

Constraints:

• 1 <= nums.length <= 50
• 1 <= nums[i] <= 50

2025-11-23
1262. Greatest Sum Divisible by Three

Topic: Array, Dynamic Programming, Greedy, Sorting
Difficulty: Medium

Problem:
Given an integer array nums, return the maximum possible sum of elements of the array such that it is divisible by three.

Example 1:

Input: nums = [3,6,5,1,8]
Output: 18
Explanation: Pick numbers 3, 6, 1 and 8 their sum is 18 (maximum sum divisible by 3).

Example 2:

Input: nums = [4]
Output: 0
Explanation: Since 4 is not divisible by 3, do not pick any number.

Example 3:

Input: nums = [1,2,3,4,4]
Output: 12
Explanation: Pick numbers 1, 3, 4 and 4 their sum is 12 (maximum sum divisible by 3).

Constraints:

• 1 <= nums.length <= 4 * 10^4
• 1 <= nums[i] <= 10^4